Field
The disclosure relates to a method, apparatus and system to improve position determination of a mobile device. Specifically, the disclosure relates to a method, apparatus and system to accurately determine position of a device inside a structure using location tokens that bind an access point to a corresponding map.
Description of Related Art
Outdoor navigation is widely deployed due to advancement in various global positioning systems (GPS). Recently, there has been an increased focus on indoor navigation and position location. Indoor navigation differs from outdoor navigation because the latter precludes receiving GPS satellite signals. As a result, effort is now directed to solving the indoor navigation problem. Conventional techniques have failed to provide an adequate scalable solution with satisfactory precision.
A solution to this problem may be based on the Time-of-Flight (ToF) measurement. ToF is defined as the overall time a signal propagates from the user to an access point (AP) and back to the user. This value can be converted into distance by dividing the signal's roundtrip travel time by two and multiplying it by the speed of light. This method is robust and scalable but requires significant hardware changes to the Wi-Fi modem and other devices. The ToF range calculation depends on determining the precise signal receive/transmit times as well as the exact location of the AP.